• Title/Summary/Keyword: clinical device

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Assessment of dose effects on image quality at chest computed radiography (흉부 CR 영상에서 선량이 화질에 미치는 영향에 대한 평가)

  • Kang, Bo-Sun
    • Journal of the Korean Society of Radiology
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    • v.5 no.6
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    • pp.421-426
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    • 2011
  • This research was accomplished to assess dose effects on image quality at computed radiography (CR). The ultimate target of the research was finding optimized exposure that provides necessary image quality for the clinical chest diagnosis. Modulation transfer function (MTF), normalized noise power spectrum (NNPS), and Noise equivalent quanta (NEQ) corresponding to the different doses were measured for the assessment of image quality. The preparation of "edge test device" used in MTF measurement and experimental geometry setup were followed by the recommendations of International Electrotechnical Commission (IEC). The experimental results show the necessary image quality can be achieved even at a half of the automatic exposure control (AEC) setting dose for chest diagnosis. It means that the patient exposure can be reduced dramatically by using optimized dose.

Toxicity of Hematoporphyrin-Coated Magnetic Ferrofluid in Rats

  • Hwang Youn-Hwan;Lim Jong-Hwan;Park Byung-Kwon;Kim Myoung-Suk;Kim Chong-Oh;Yun Hyo-In
    • Toxicological Research
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    • v.22 no.1
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    • pp.55-59
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    • 2006
  • The purpose of this study was to investigate the toxicity of hematoporphyrin-coated magnetic ferrofluid (HP-MF) through intravenous administration in Sprague-Dawley rats. Each group was treated with either saline, or the HP-MF at 0.5, 1, 1.5, 2 and 4 ml/kg body weight (b.w.) for the observation of survival rate, clinical symptoms, laboratory values and histopathological findings. In this study, HP-MF was evaluated for the survival rates, symptoms, laboratory values and histopathological examination after treatments. The result revealed that the animals in the group of HP-MF at 2 and 4 ml/kg b.w. showed some lethality. In serum biochemistry, the levels of AST, ALT and ALP were increased in the MF and HP-MF treated groups. However, histopathological examination for the suspected organs showed no evidence of hepatotoxicity and nephrotoxicity of typical iron poisoning. Though the toxicity of HP-MF was higher than that of HP, long retention of hematoporphyrin via HP-MF provides additional benefit over conventional hematoporphyrin. HP-MF could be utilized as a potential photodynamic agent in cancer therapy. It is suggested to develop an efficient external magnetic device to attract hematoporphyrin in the target site, thereby enabling to administering a small amount of HP-MF.

Comparison of Ligasure Versus Conventional Surgery for Curative Gastric Cancer Resection: a Meta-Analysis

  • Hu, Tian-Peng;He, Xiang-Hui;Meng, Zhao-Wei;Jia, Qiang;Tan, Jian;Li, Xue
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.4
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    • pp.2049-2053
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    • 2016
  • Background: The LigaSure vessel sealing system has been proposed to save operation time and reduce intraoperative blood loss for various surgeries. However, its usage for gastric cancer is still controversial. The aim of the present meta-analysis was to compare the effectiveness of LigaSure with conventional surgery in gastrectomy. Materials and Methods: Sources were retrieved from the Cochrane Library, MEDLINE, EMBASE, SCOPUS and Google Scholar until February, 2015. All randomized controlled trials comparing LigaSure with conventional surgery in curative gastric cancer resection were selected. After data extraction, statistics were performed by Review Manager 5.1 software. Results: Three eligible randomized controlled trials were evaluated, with a total of 335 patients. The quality of the included trials was good, yet some methodological and clinical heterogeneity existed. There were no significant differences between the LigaSure and conventional groups in operative time (weighted mean difference [WMD], -22.95 minutes; 95% confidence interval [CI], [-59.75, 13.85]; P = 0.22), blood loss (WMD, -45.8 ml; 95% CI, [-134.5, 42.90]; P = 0.31), nor the incidence of surgical complications (odds ratio, 1.18; 95% CI, [0.68, 2.05]; P = 0.54). But there was a longer duration of hospital stay in LigaSure group (WMD, 1.41 days; 95% CI, [0.14, 2.68]; P = 0.03). Conclusions: All available randomized evidence has been summarized. LigaSure does not confer significant advantage over conventional surgery for curative gastric cancer resection. The usefulness of the device may be limited in gastrectomy. But, more trials are needed for further assessment of the LigaSure system for gastric cancer.

Transcatheter closure of small ductus arteriosus with amplatzer vascular plug

  • Cho, Eun Hyun;Song, Jinyoung;Kang, I-Seok;Huh, June;Lee, Sang Yoon;Choi, Eun Young;Kim, Soo Jin
    • Clinical and Experimental Pediatrics
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    • v.56 no.9
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    • pp.396-400
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    • 2013
  • Purpose: The purpose of this study was to share our experience of transcatheter closure of small patent ductus arteriosus (PDA) by using an Amplatzer vascular plug (AVP). Methods: We reviewed the medical records of 20 patients who underwent transcatheter closure at Samsung Medical Center and Sejong General Hospital from January 2008 to August 2012. The size and shape of the PDAs were evaluated by performing angiograms, and the PDA size and the AVP devices size were compared. Results: The mean age of the patients was $54.9{\pm}45.7$ months old. The PDAs were of type C (n=5), type D (n=12), and type E (n=3). The mean pulmonary end diameter of the PDA was $1.7{\pm}0.6$ mm, and the aortic end diameter was $3.6{\pm}1.4$ mm. The mean length was $7.3{\pm}1.8$ mm. We used 3 types of AVP devices: AVP I (n=5), AVP II (n=7), and AVP IV (n=8). The ratio of AVP size to the pulmonary end diameter was $3.37{\pm}1.64$, and AVP size/aortic end ratio was $1.72{\pm}0.97$. The aortic end diameter was significantly larger in those cases repaired with AVP II than in the others (P=0.002). The AVP size did not significantly correlate with the PDA size, but did correlate with smaller ratio of AVP size to aortic end diameter ($1.10{\pm}0.31$, P=0.032). Conclusion: Transcatheter closure of small PDA with AVP devices yielded satisfactory outcome. AVP II was equally effective with smaller size of device, compared to others.

Significance of C-Reactive Protein and Transcranial Doppler in Cerebral Vasospasm Following Aneurysmal Subarachnoid Hemorrhage

  • Hwang, Sung-Hwan;Park, Yong-Sook;Kwon, Jeong-Taik;Nam, Taek-Kyun;Hwang, Sung-Nam;Kang, Hyun
    • Journal of Korean Neurosurgical Society
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    • v.54 no.4
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    • pp.289-295
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    • 2013
  • Objective : Cerebral vasospasm is a common and potentially devastating complication of aneurysmal subarachnoid hemorrhage (aSAH). Inflammatory processes seem to play a major role in the pathogenesis of vasospasm. C-reactive protein (CRP) constitutes a highly sensitive inflammatory marker. Elevation of serum CRP levels has been demonstrated in patients with aSAH. The purpose of the current study was to evaluate the possible relationship between CRP levels in the serum and transcranial Doppler (TCD) and the development of vasospasm in patients with aSAH. Methods : A total of 61 adult patients in whom aSAH was diagnosed were included in the study from November 2008 to May 2011. The patients' demographics, Hunt and Hess grade, Fisher grade, CT scans, digital subtraction angiography studies, and daily neurological examinations were recorded. Serial serum CRP measurements were obtained on days 1, 3, 5, 7, 9, 11 and 13 and TCD was measured on days 3, 5, 7, 9, 11 and 13. All patients underwent either surgical or endovascular treatment within 24 hours of their hemorrhagic attacks. Results : Serum CRP levels peaked on the 3rd postoperative day. There were significant differences between the vasospasm group and the non-vasospasm group on the 1st, 3rd and 5th day. There were significant differences between the vasospasm group and the non-vasospasm group on the 3rd day in the mean middle cerebral artery velocities on TCD. Conclusion : Patients with high levels of CRP on the 1st postoperative day and high velocity of mean TCD on the 3rd postoperative day may require closer observation to monitor for the development of vasospasm.

Changes in maximum lip-closing force after extraction and nonextraction orthodontic treatments

  • Choi, Tae-Hyun;Kim, So-Hyun;Kim, Cheul;Kook, Yoon-Ah;Larson, Brent E.;Lee, Nam-Ki
    • The korean journal of orthodontics
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    • v.50 no.2
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    • pp.120-128
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    • 2020
  • Objective: The aims of the present study were to evaluate the changes in the maximum lip-closing force (MLF) after orthodontic treatment with or without premolar extractions and verify the correlation of these changes with dentoskeletal changes. Methods: In total, 17 women who underwent nonextraction orthodontic treatment and 15 women who underwent orthodontic treatment with extraction of all four first premolars were included in this retrospective study. For all patients, lateral cephalograms and dental models were measured before (T0) and after (T1) treatment. In addition, MLF was measured at both time points using the Lip De Cum LDC-110R® device. Statistical analyses were performed to evaluate changes in clinical variables and MLF and their correlations. Results: Both groups showed similar skeletal patterns, although the extraction group showed greater proclination of the maxillary and mandibular incisors and lip protrusion compared to the nonextraction group at T0. MLF at T0 was comparable between the two groups. The reduction in the arch width and depth and incisor retroclination from T0 to T1 were more pronounced in the extraction group than in the nonextraction group. MLF in the extraction group significantly increased during the treatment period, and this increase was significantly greater than that in the nonextraction group. The increase in MLF was found to be correlated with the increase in the interincisal angle and decrease in the intermolar width, arch depth, and incisor-mandibular plane angle. Conclusions: This study suggests that MLF increases to a greater extent during extraction orthodontic treatment than during nonextraction orthodontic treatment.

Evaluation of augmented alveolar bone with vertical alveolar distraction osteogenesis and implant installation (수직 치조골 신장술 후 증대된 치조골과 임플란트의 예후 평가)

  • Shet, Uttom Kumar;Kook, Min-Suk;Jung, Seung-Gon;Oh, Hee-Kyun
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.37 no.5
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    • pp.421-428
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    • 2011
  • Introduction: The purpose of this study was to evaluate the clinical result of vertical alveolar distraction, especially the distracted alveolar bone and installed implants. Materials and Methods: Twenty-one patients who have been received the vertical alveolar distraction and implant installation on 22 areas (3 maxilla and 19 mandible) using intraoral alveolar distraction device were examined. After consolidation period of 3-4 months, distraction devices were removed and 91 implants were installed in the distracted alveolar bone. The distracted bone and implants were evaluated clinically and radiographically. Results: Mean height of distracted alveolar bone was $7.5{\pm}3.2$ mm (range: 2.5-15.0 mm). Mean follow-up period after completion of the distraction was 3.1 years (range: 1.4-11.5 years). Mean resorption of distracted alveolar bone was $1.6{\pm}1.8$ mm. The success and survival rates of implants was 95.3% and 100%, respectively. Conclusion: Results of this study indicate that vertical alveolar distraction procedure is a useful and stable method for alveolar ridge augmentation and implantation.

Design and Implementation of the Web-based Monitoring System for an Artificial Heart (웹 기반 인공심장 모니터링 시스템의 설계와 구현)

  • 정진한;최재순;이지훈;민병구
    • Journal of Biomedical Engineering Research
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    • v.23 no.2
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    • pp.131-137
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    • 2002
  • The remote monitoring system including hemodynamic information and pump status of the implanted animal could be helpful during the in vivo experiment or clinical trial for an artificial heart Implantation. In order to monitor the course of the in vivo experiment continuously and anywhere, web-based remote monitoring system was developed, which can monitor pressures(AoP, LAP, RAP, PAP) and flow information as well as the pump operating conditions. The system consists of data sending, storing viewer part. The data sending part was constructed using component object model and the viewer part was constructed using the Java applet. In addition, the dialog box was introduced to communicate earth other instantly and the alarming function was also introduced when the hemodynamic values were out of the desired ranges. The developed remote monitoring system was applied during the in vivo experiment of the BVAD (Bi-ventricular Assist Device) implantation for 1 month and showed designed work without failure.

Availability of peripheral inserted central catheters in severe hemophilia patients with inhibitors (중증 혈우병 항체 환자에서 시행한 말초삽입 중심혈관 카테터의 유용성)

  • Park, Youngshil
    • Clinical and Experimental Pediatrics
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    • v.51 no.12
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    • pp.1359-1362
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    • 2008
  • The most effective treatment strategy for patients with hemophilia is replacement therapy with FVIII or FIX concentrates, which usually requires long-term, uncomplicated venous access. However, central venous access device (CVADs, ports) insertion requires inpatient admission and general anesthesia, and presents some problems regarding health insurance coverage. Peripherally inserted central catheters (PICCs) were inserted in two severe hemophilia patients aged 7 and 11 years with high titers of inhibitors. They experienced frequent bleeding episodes and required replacement therapy, which eventually resulted in difficulty in acquiring venous line access. Factor VIII activity was below 1%, and inhibitor titers were 160 and 26.3 BU/ml. In an outpatient setting, PICC lines are easily placed by radiological guidance and require local anesthesia alone. PICC has been feasible, in particular, for hemophilia patients with frequent bleeding episodes.

BellaGel breast implant: 6-Year results of a prospective cohort study

  • Oh, Joon Seok;Jeong, Jae Hoon;Myung, Yujin;Oh, Jeongseok;Kang, Shin Hyeok;Park, Eonju;Kim, Ara;Bang, Sa Ik;Heo, Chan Yeong
    • Archives of Plastic Surgery
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    • v.47 no.3
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    • pp.235-241
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    • 2020
  • Background This is the first clinical study conducted among Asian women using breast implants manufactured by an Asian company. Four-year data regarding the safety and efficacy of BellaGel breast implants have already been published, and we now report 6-year data. Methods This study was designed to take place over 10 years. It included 103 patients who underwent breast reconstruction or augmentation using BellaGel breast implants. The rates of implant rupture and capsular contracture were measured and analyzed to evaluate the effectiveness of the breast implant. Results At patients' 6-year postoperative visits, the implant rupture and capsular contracture rates were 1.15% and 2.30%, respectively. The implant rupture rate was 3.77% among reconstruction cases and 0% among augmentation cases. The capsular contracture rate was 5.66% among reconstruction cases and 0.83% among augmentation cases. Conclusions The 6-year data from this planned 10-year study suggest that the BellaGel cohesive silicone gel-filled breast implant is an effective and safe medical device that can be used in breast reconstruction and augmentation.